1. Field of the Invention
The present invention relates to a pallet exchange device adapted to exchange a loaded or unloaded pallet with an unloaded or loaded pallet, respectively, by the forward and backward movement of a remote-controlled fork lift truck and by the vertical movement of forks thereof.
2. Description of the Prior Art
So far when a loaded or unloaded pallet carried by a remote-controlled fork lift truck is replaced with an loaded or unloaded pallet, a loaded or unloaded pallet 3 carried by a fork 2 of a remote-controlled fork lift truck 1 is left on an unloading stand 4 by a series of operations consisting of first moving a fork lift truck backward (that is, upward in FIG. 1), lowering the fork 2 and then moving the fork lift truck 1 forward (that is, downward in FIG. 1). Thereafter, the fork lift truck 1 is shifted to the left in FIG. 1 and then moved backward. Next the fork 2 is raised so that the fork 2 carries an unloaded or loaded pallet 5.
The fork lift truck 1 must be moved forward and backward twice and shifted laterally twice. As a consequence, a pallet exchange time cycle is long and additional spaces where loaded and unloaded pallets are stacked are needed. In addition, in the case of a remote-controlled fork lift truck, a lateral movement means for shifting the fork lift truck laterally is needed. As a result, the conventional pallet exchange devices have economical disadvantages in respect to floor space and equipment.